1. Field of the Invention
This invention relates to an apparatus and a system for at least recording information on or reproducing information from a card-shaped recording medium.
2. Related Background Art
There have been a number of optical information recording/reproducing apparatus developed recently and adapted to use a recording medium, such as an optical file or a compact disk. However, attention is now being paid to card-shaped optical information recording media (hereinafter referred to as optical cards) that are dimensionally small and hence easy to carry but have a large memory capacity. Optical cards are advantageous not only because they have a large memory capacity but also because they can be duplicated with ease at low cost. Other advantages of optical cards include that they are writing-once-type recording media and hence the information recorded thereon can hardly be altered fraudulently to make them highly reliable. A large storage capacity optical card can be made as small and lightweight as a credit card and therefore there is anticipated a large demand for such optical cards.
An optical card is a medium on which information can be recorded by irradiating it with light and from which information can be retrieved also by irradiating it with light. More specifically, a finely converged light spot is moved back and forth on the optical card to record information on and reproduce information from it. Information can be recorded in the form of rows of optically detectable recording pits by modulating the light spot according to the information to be recorded. Control techniques such as auto-focusing (hereinafter referred to as AF) control and auto-tracking (hereinafter referred to as AT) control are known as means for accurately recording information in a predetermined region. With AT control, the light spot is positionally controlled in a direction perpendicular to its scanning direction on the surface of the optical card. AF control is used to positionally control the light spot in a direction vertical to the surface of the optical card. Of course, these control techniques are also required to reproduce information from the optical card.
In recent years, IC cards are also attracting attention because of the information security feature they have. Two types of IC cards are known to date; the contact type and the non-contact type. A non-contact type IC card requires the use of an electromagnetic wave as a medium for transmitting information from the IC card and a recording/reproducing apparatus and vice versa. A pair of coils are arranged face to face between the IC card and the apparatus to generate and receive an induced field, which field is used as a medium for transmitting information. An IC card typically comprises an IC chip and a coil arranged as laminate by using vinyl chloride or some other appropriate material for keeping them in shape and binding them together. It may or may not contain a power source, although battery-less type IC cards containing no power source for recording/reproducing operations are in the main stream because they can be made very thin and have a long service life (but they may contain a battery necessary for preventing the stored information from expiring).
The applicant of the present patent application has invented a hybrid card having both the advantages of an optical card and those of an IC card and comprising a non-contact IC memory region and an optical recording region and also a hybrid reader/writer for recording information on and reproducing information from such a hybrid card and applied for patent for the invention in Japanese Patent Application No. 9-192366.
The object of the present invention is to provide an apparatus and a system adapted to at least record information on or reproduce information from such a hybrid card. According to the invention, it is possible to realize an apparatus and a system with which the focusing control and the tracking control of the optical beam irradiated on the optical recording region of a hybrid card is minimally affected by the electromagnetic induction that arises in the operation of storing information in or retrieving the information stored in the IC memory region of the hybrid card.
According to an aspect of the invention, the above object is achieved by providing an apparatus for at least recording information on or reproducing information from a card-shaped recording medium having an optical recording region including a track, an IC memory region and a communication antenna coil connected to the IC memory region, the apparatus comprising:
an optical head unit for irradiating the optical recording region of the medium with a focused beam of light in order to at least record information on or reproduce information from it;
a control circuit for exerting at least tracking control or focusing control on the beam of light;
an apparatus-side antenna coil arranged opposite the antenna coil of the medium;
a reader/writer for at least storing information in or reading information from the IC memory region of the medium by way of the apparatus-side antenna coil; and
a processing circuit for controlling the operation of the optical head unit, the control circuit and the reader/writer;
the processing circuit controlling the reader/writer so as not to store information in nor read information from the IC memory region of the medium during the period where the control circuit is exerting at least tracking control or focusing control on the beam of light.
According to another aspect of the invention, the above object is achieved by providing a system for at least recording or reproducing information comprising:
a card-shaped recording medium including an optical recording region having a plurality of tracks, an IC memory region, a telecommunication antenna coil connected to the IC memory region, the medium having an area where part of the optical recording region is overlapped by the antenna coil in a direction perpendicular to the surface of the medium;
an optical head for irradiating a converged beam of light on the optical recording region of the medium for at least recording or reproducing information;
a control circuit for exerting at least tracking control or focusing control on the optical beam;
an apparatus-side antenna coil disposed vis-a-vis the antenna coil of the medium;
a reader/writer for at least storing information in or reproducing information from the IC memory region of the medium by way of the apparatus-side antenna coil; and
a control circuit for controlling the operation of the optical head so as to at least record information in or reproduce information from an area of the optical recording region of the medium other than the area overlapped by the antenna coil.